2.14 Immunohistochemistry staining
Paraffin skin sections (5 µm in thickness) were deparaffinized and
rehydrated, and subsequently treated with antigen retrieval solution for
6 min at 96 °C. The sections were stained with PCNA antibody (Abcam;
Cat#ab29; 1:200) at 4 °C overnight, and then reprobed with
goat-anti-rabbit HRP-conjugated antibody for 2 h at room temperature.
All antibodies were diluted with PBS containing 1% BSA. The staining
was visualized by reacting with 3, 3-diaminobenzidine (1:20) (DAB; Sigma
Chemical Co., USA), and then the nuclei were stained with hematoxylin
(Solarbio Science & Technology, China). Results were evaluated by Nikon
Eclipse Ni light microscopy.